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<td ><a href="../qtdoc/index.html">Qt 5.12</a></td><td ><a href="qtquick-index.html">Qt Quick 模块</a></td><td ><a href="qtquick-qmlmodule.html">QML类型</a></td><td >TrailEmitter QML 类型</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtquick-index.html">Qt 5.12.3 参考指南</a></td>
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<h3><a name="toc">目录</a></h3>
<ul>
<li class="level1"><a href="#properties">属性</a></li>
<li class="level1"><a href="#signals">信号</a></li>
<li class="level1"><a href="#details">详细信息</a></li>
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<h1 class="title">TrailEmitter QML 类型</h1>
<span class="subtitle"></span>
<!-- $$$TrailEmitter-brief -->
<p>Emits logical particles from other logical particles. <a href="#details">更多...</a></p>
<!-- @@@TrailEmitter -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> 导入语句：</td><td class="memItemRight bottomAlign"> import QtQuick.Particles 2.12</td></tr></table></div><ul>
<li><a href="qml-qtquick-particles-trailemitter-members.html">所有成员的列表，包括继承成员</a></li>
</ul>
<a name="properties"></a>
<h2 id="properties">属性</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#emitHeight-prop">emitHeight</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#emitRatePerParticle-prop">emitRatePerParticle</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#emitShape-prop">emitShape</a></b></b> : Shape</li>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#emitWidth-prop">emitWidth</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#follow-prop">follow</a></b></b> : string</li>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#velocityFromMovement-prop">velocityFromMovement</a></b></b> : qreal</li>
</ul>
<a name="signals"></a>
<h2 id="signals">信号</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtquick-particles-trailemitter.html#emitFollowParticles-signal">emitFollowParticles</a></b></b>(Array <i>particles</i>,  Particle <i>followed</i>)</li>
</ul>
<!-- $$$TrailEmitter-description -->
<a name="details"></a>
<h2 id="details">详细信息</h2>
<p>This element emits logical particles into the <a href="qml-qtquick-particles-particlesystem.html">ParticleSystem</a>, with the starting positions based on those of other logical particles.</p>
<!-- @@@TrailEmitter -->
<h2>属性文档</h2>
<!-- $$$emitHeight -->
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<tr valign="top" class="odd" id="emitHeight-prop">
<td class="tblQmlPropNode"><p>
<a name="emitHeight-prop"></a><span class="name">emitHeight</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>The height in pixels the <a href="qml-qtquick-particles-trailemitter.html#emitShape-prop">emitShape</a> is scaled to. If set to <a href="qml-qtquick-particles-trailemitter.html">TrailEmitter</a>.ParticleSize, the height will be the current size of the particle being followed.</p>
<p>Default is 0.</p>
</div></div><!-- @@@emitHeight -->
<br/>
<!-- $$$emitRatePerParticle -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="emitRatePerParticle-prop">
<td class="tblQmlPropNode"><p>
<a name="emitRatePerParticle-prop"></a><span class="name">emitRatePerParticle</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"></div></div><!-- @@@emitRatePerParticle -->
<br/>
<!-- $$$emitShape -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="emitShape-prop">
<td class="tblQmlPropNode"><p>
<a name="emitShape-prop"></a><span class="name">emitShape</span> : <span class="type"><a href="qml-qtquick-shapes-shape.html">Shape</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>As the area of a <a href="qml-qtquick-particles-trailemitter.html">TrailEmitter</a> is the area it follows, a separate shape can be provided to be the shape it emits out of. This shape has width and height specified by <a href="qml-qtquick-particles-trailemitter.html#emitWidth-prop">emitWidth</a> and <a href="qml-qtquick-particles-trailemitter.html#emitHeight-prop">emitHeight</a>, and is centered on the followed particle's position.</p>
<p>The default shape is a filled Rectangle.</p>
</div></div><!-- @@@emitShape -->
<br/>
<!-- $$$emitWidth -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="emitWidth-prop">
<td class="tblQmlPropNode"><p>
<a name="emitWidth-prop"></a><span class="name">emitWidth</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>The width in pixels the <a href="qml-qtquick-particles-trailemitter.html#emitShape-prop">emitShape</a> is scaled to. If set to <a href="qml-qtquick-particles-trailemitter.html">TrailEmitter</a>.ParticleSize, the width will be the current size of the particle being followed.</p>
<p>Default is 0.</p>
</div></div><!-- @@@emitWidth -->
<br/>
<!-- $$$follow -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="follow-prop">
<td class="tblQmlPropNode"><p>
<a name="follow-prop"></a><span class="name">follow</span> : <span class="type"><a href="../qtqml/qml-string.html">string</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>The type of logical particle which this is emitting from.</p>
</div></div><!-- @@@follow -->
<br/>
<!-- $$$velocityFromMovement -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="velocityFromMovement-prop">
<td class="tblQmlPropNode"><p>
<a name="velocityFromMovement-prop"></a><span class="name">velocityFromMovement</span> : <span class="type">qreal</span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>If this value is non-zero, then any movement of the emitter will provide additional starting velocity to the particles based on the movement. The additional vector will be the same angle as the emitter's movement, with a magnitude that is the magnitude of the emitters movement multiplied by velocityFromMovement.</p>
<p>Default value is 0.</p>
</div></div><!-- @@@velocityFromMovement -->
<br/>
<h2>Signal Documentation</h2>
<!-- $$$emitFollowParticles -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="emitFollowParticles-signal">
<td class="tblQmlFuncNode"><p>
<a name="emitFollowParticles-signal"></a><span class="name">emitFollowParticles</span>(<span class="type">Array</span> <i>particles</i>,  <span class="type"><a href="qml-qtquick-particles-particle.html">Particle</a></span> <i>followed</i>)</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal is emitted when particles are emitted from the <i>followed</i> particle. <i>particles</i> contains an array of particle objects which can be directly manipulated.</p>
<p>The corresponding handler is <code>onEmitFollowParticles</code>. If you use this signal handler, emitParticles will not be emitted.</p>
</div></div><!-- @@@emitFollowParticles -->
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